Has anyone done one of these? I haven't got my grain mill yet, and thought these would be a good substitute, instead of trying to find places that sell 1/4# grain increments. What efficiency are these kits based on? Is there a good crush on the grains?

I concur with everyone. I get all my grains from AHS and I've never had a problem with the grains (once or twice I messed up on procedural things). I prefer AHS for a couple reasons:
1. They sell grains in increments smaller than a pound

2. You can get all the grains packaged together in one bag. Makes things easier, especially with large grain bills.

I did do one of their kits once and was really impressed with the overall quality of the resulting beer.

Sweet, with hop prices the way they are I think these kit's will be the way to go. I just ordered the ingredients to make Yuri's Floor Kill Ale, right down to the pacman yeast, total $50.99 Grain mill here I come!